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61.
船舶管理信息系统研发   总被引:6,自引:0,他引:6  
郑士君  黄爱平  沈忠  吴雨华  董建华  董晗 《机电设备》2005,22(6):I0001-I0005
经校企双方多年合作,采用先进船舶管理理念和标准化代码、运用国际先进的船岸通讯技术开发出的船舶管理信息系统完全符合国际、国内船舶管理行业的业务要求,该系统的研发成功对我国航运界实现船舶信息化和数字化管理起到了积极作用.  相似文献   
62.
Road transport of today has a substantial need for a better information system. The European research programmes PROMETHEUS and DRIVE offer the prospect of new techniques and strategies. The role of information in road transport is analysed from the viewpoint of the individual drivers and from the viewpoint of the traffic manager. All necessary information must be brought together and a complex data‐bank system for road transport should be installed. As examples of advanced information systems the concepts of the ‘Wolfsburg wave’ for in‐car speed recommendation and of the LISB field experiment in route guidance in Berlin are explained.  相似文献   
63.
ABSTRACT

In this paper we focus on the estimation of crowding in public transport – specifically urban rail systems – and its effect on perceived comfort. It is different from similar studies in the method it employs for estimating crowding levels in vehicles. Specifically, we formulate a function of time and location, which uses only passenger embarking data to estimate the number of passengers in vehicles. Then we convert the estimated crowding values into perceived discomfort levels by trip section. Our method depends on hourly seasonality assumptions but provides good estimates of crowding in urban rail systems even when passenger alighting data is not available. We illustrate the implementation of our model with the example of the Istanbul Metro system.  相似文献   
64.
船舶法定证书是指由有关公约的一个缔约国或由代表缔约国经认可的机构,或由船旗国或由船旗国经认可的机构,经法定检验后直接签发的,包括准确和有效的日期,符合有关公约、规则规定并载明船舶、船员和设备细目的格式化证书。  相似文献   
65.
There is a broad body of theoretical and empirical literature dealing with trip chaining behaviour. This paper adds to the literature while focusing on the impact of activity chaining on the duration of time spent on individual purposes. Two questions in particular are addressed: first, does an additional purpose added to a trip chain affect the duration of the activities included? Second, is there any pattern of included activities that explains differences in duration? Duration data models are employed using German data. We find evidence that the number of purposes influences duration significantly. Leisure, shopping and personal business activities are affected by the occurrence of obligatory activities (work, school/university). We cannot find any evidence that personal business or leisure activities influence the duration of shopping, whereas the opposite is supported. Therefore, in terms of daily activities, obligatory and shopping activities are superior to leisure and personal business. We conclude that activity chaining and especially the pattern of combined purposes affect the duration of activities allocated to single purposes while controlling for a wide range of other explanatory variables. The results can be used in transport and simulation models.  相似文献   
66.
基于兴波阻力的薄船理论,作者曾提出用兰金体波幅函数(RWAF)代替实际船型的波幅函数,确定了高速双体船片体间的阻力干扰因子,从而可计算得到双体船的兴波阻力.本文将该方法用于高速三体船侧体与主体之间的兴波阻力干扰计算,以探讨主、侧体尺度及相对位置变化对于兴波阻力干扰因子τO、τOM的影响及其变化规律.基于这一研究结果,可实现用单体船阻力的实验资料,经过侧体、主体间的兴波干扰影响理论修正,来估算高速三体船的阻力;同时可用于对于最小阻力三体船片体尺度与布局之优化.  相似文献   
67.
68.
概述了在铁道车辆制造领域引入产品平台这一生产管理思想,分析了从汽车领域引入标准化加工的可能性,阐述了铁道车辆工业开始运用的情况,并介绍了一个功能强大的IT弹性开发工具,利用该工具,可允许按照用户的特殊要求,对完全参数化的车辆模型进行快速修改,并可使用标准化的程序,生产出适应用户有特殊要求的车辆。  相似文献   
69.
This paper is on the design of cooperative adaptive cruise control systems for automated driving of platoons of vehicles in the longitudinal direction. Longitudinal models of vehicles with simple dynamics, an uncertain first order time constant and vehicle to vehicle communication with a communication delay are used in the vehicle modeling. A robust parameter space approach is developed and applied to the design of the cooperative adaptive cruise control system. D-stability is chosen as the robust performance goal and the feedback PD controller is designed in controller parameter space to achieve this D-stability goal for a range of possible longitudinal dynamics time constants and different values of time gap. Preceding vehicle acceleration is sent to the ego vehicle using vehicle to vehicle communication and a feedforward controller is used in this inter-vehicle loop to improve performance. Simulation results of an eight vehicle platoon of heterogeneous vehicles are presented and evaluated to demonstrate the efficiency of the proposed design method. Also, the proposed method is compared with a benchmark controller and the feedback only controller. Time gap regulation and string stability are used to assess performance and the effect of the vehicle to vehicle communication frequency on control system performance is also investigated.  相似文献   
70.
The application of the X-ray diffraction method is introduced to solve the problem of inhomogeneous deformation fields in the specimens used for sheet metal characterization. In this method, strains are measured on one side of a specimen with optical measurement systems. On the other side, loading stresses on a specimen are captured with an X-ray diffractometer mounted on a universal testing machine. By this way, the whole stress-strain history of a material point is tracked during testing. The method was first applied to uniaxial tension tests, whereby the applicability of the theory of stress factors and effective X-ray elastic constants were tested. The relaxation behavior of a sheet material which shows itself as stress drops during in-situ experimentation was characterized and compensated by a visco-plastic material model for different stress states. The proposed method was applied to characterize aluminum alloy AA5182 under plane strain tension and shear conditions and the results were compared with the conventionally obtained yield locus. Numerical analyses of a workpiece with the Vegter and Yld2000-2D material models show that the enriched yield locus definition with accurate plane strain tension and shear stresses captures the experimentally obtained surface strains more precisely.  相似文献   
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